The invention relates to nanomaterials comprising a plurality of nanoparticles. More particularly, the invention relates to scintillator materials comprising a plurality of nanoparticles.
Nanomaterials are used in processing steps in the fabrication of scintillators for imaging applications and as phosphors for lighting applications. Known scintillator materials are thallium-doped sodium iodide (NaI:Tl), cesium fluoride (CsF), barium fluoride (BaF2), and bismuth germanate (Bi4Ge3O12 or “BGO”). NaI:Tl has a good stopping power, but a long decay constant of about 250 nsec (nanoseconds). CsF has relatively poor stopping power of about 0.43 cm−1 and is highly hygroscopic. BGO has a relatively good stopping power but a relatively low light output and a long decay constant (of about 300 nsec). Although BaF2 is not as hygroscopic as CsF, it has a poor stopping power similar to that of CsF and a much longer decay constant (of about 620 nsec).
Various synthesis routes, such as sol-gel, colloidal, precipitation, combustion synthesis, and solid-state methods have been used to produce nanomaterials. Combustion synthesis typically involves the choice of a nitrate precursor, the addition of a fuel to the nitrate precursor and ignition of the nitrate precursor-fuel mixture to provide an oxide based nanomaterial. However, available combustion synthesis methods have not been able to provide nanomaterials comprising a broad range of materials, such as phosphates, silicates, hafnates, and aluminates of alkali earth metals, lanthanides and transition metals. Therefore, what is needed is a nanomaterial comprising a plurality of nanoparticles wherein the plurality of nanoparticles comprises the abovementioned materials and is made by combustion synthesis. What is also needed is a method of making a scintillator nanomaterial comprising oxides, phosphates, silicates, hafnates, and aluminates of such metals.